The present invention relates generally to light transfer devices and systems, and more particularly to a device used with a light transfer system for efficiently transferring light from a light source to an image plane.
It is common practice to collect light and transmit light or electromagnetic energy from one location to another location in the form of rays or beams. In the past, light, which has been radiated in many directions, has been collected, and then relayed, focused or scanned by mirrors, lenses, and/or prisms. Optical light beams diverge and broaden, but they can be refocused by the use of lenses and mirrors. When using lenses, atypical condenser system (e.g., lens to collect light) projects the source of light onto an image plane. Since the light source is imaged, the light source should be generally uniform to enhance uniformity at the image plane being illuminated. However, there are several drawback and disadvantages to such imaging systems. For example, the collection angle in condenser systems is generally low compared to other systems. Also, the condenser systems generally have a plurality of optical elements, and as such, increases the complexity of mechanically mounting each component of the system, and can increase the overall cost of the system. Furthermore, the light beam can be easily obstructed or scattered by various objects.
Another conventional system is guided-wave optical devices. Conventional guided-wave optical devices transmit light through dielectric conduits, which can provide long distance light transmission without the need or use of relay lenses. Generally, a guided-wave optical device is a light conduit that is configured as either a slab, strip, or cylinder of dielectric material, and generally having a rectangular vertical cross sectional shape along its respective longitudinal axis. These guided-wave optic devices utilize internal reflections to integrate and transport light to an image plane. Light reflects off the interface between the dielectric material and outside material (e.g., a material with an index of refraction less than the dielectric material, such as glass with an additive, or air) interface.
In use, however, light exiting these guided-wave optical devices are not generally focused, and the level of irradiance of the image plane object can rapidly decrease as the distance between light source and the image plane increases. This can be due to a number of factors, including light being lost or leaking out of the guided-wave optical device due to refraction because of a lower than desired collection angle. Materials are generally softer and more difficult to machine. Furthermore, such materials can be more expensive and can be a more hazy material.
As can be seen, currently available optical devices and systems have a number of shortcomings that can greatly reduce the amount of light and/or focus of the light being transmitted from the light source to the image plane. Moreover, light being emitted from conventional devices and systems is not always uniform and any source imperfections are transmitted through the device and system.
Briefly summarized, the present invention comprises a waveguide device for transmitting light. In one embodiment of the present invention, the present invention comprises a waveguide device having a light transmitting body. The body includes a first surface and a second surface, and a longitudinal axis. At least one of the first and second surfaces, and preferably both surfaces, are configured to be non-parallel to the longitudinal axis. Furthermore, the first surface is configured to be non-parallel to the second surface. In a particular embodiment, the body of the waveguide device is configured in a generally elliptical shape along the longitudinal axis, whereby a proximal portion of the waveguide device is generally symmetrical with a distal portion.
To efficiently and effectively transmit light, the body of the waveguide device preferably comprises a dielectric material, such as either a plastic material (e.g., acrylic), or a glass material. In one embodiment, the body of the waveguide device is a solid piece of material. In another embodiment, the body may include a hollow chamber therein.
The first and/or second surfaces of the body may also include a reflective coating material. The coating may be bare gold, gold, aluminum, silver, mixtures thereof, or any other suitable reflective material.
The body of the waveguide of the present invention may also include an end surface that is configured to be parallel to the transverse axis of the waveguide device.
In another embodiment, the present invention comprises may include an optical transfer system having a light source operable to produce electromagnetic energy, and an elliptically configured waveguide device operable to receive electromagnetic energy from the light source. The waveguide device can direct the electromagnetic energy to an image plane. The waveguide device includes a body having a first surface and a second surface and a longitudinal axis, at least one of the first and second surfaces is configured to be non-parallel to the longitudinal axis. The waveguide device may also include an end portion provided adjacent the image plane, and/or an end that is positioned abutting the light source.
In yet another embodiment, the present invention may include a digital film processing system. The digital film processing system has at least one light source operable to produce light, and an elliptically configured waveguide device operable to direct light from at least one light source, such as a source of electromagnetic radiation, to a photographic media. The digital film processing system also includes at last one optical sensor operable to detect light from the photographic media and a computer processor connected to the at least one sensor and operable to produce a digital image. The at least one optical sensor operates to detect reflected and/or transmissive light from the photographic media.